Alphabetizing users by last name field

I’ve done quite a bit of research into this and done some searching, but still haven’t found a good solution – or any solution really.

Basically have a directory of users setup and want to organize them by last name. However, it would be preferable to organize them by a bp_profile_field setup with their last name since some members have surnames or go by Jr. (ex: Van Doren, Gonzalez Jr.).

Basically looking to organize users alphabetically by a bp_profile_field.